Users of printing devices desire color consistency and color accuracy in printed materials despite changes, or equipment changes in the printing environment or equipment (e.g. use of multiple printing devices, changes in media, inks, replacement of printheads). For example, a commercial user sometimes prints company logos and other artwork comprising specific color schemes that consumers associate with that user's products. Such a user often desires the capability to accurately and consistently print specific shade, tint and hues notwithstanding changes in the printing environment and/or utilization of multiple printing devices.
To maintain such color consistency and color accuracy during printing, current printing devices may incorporate a spectrophotometer to provide online color profiling capability. To provide the desired color consistency, the spectrophotometer may utilize color sensing optics and electronics to measure a profiling patch created by the printing device in which the spectrophotometer is housed. To provide the desired color accuracy, the spectrophotometer may utilize color sensing optics and electronics to measure an internal color reference to calibrate the spectrophotometer to a known standard. These online measurements may then be used to make adjustments to the printing device to maintain color consistency and color accuracy in the final product.
The performance of a spectrophotometer degrades as microscopic droplets of ink floating inside the printer (aerosol) stain and create deposits on the surfaces of the color-sensing optics and/or the color calibration tile. Other debris, such as bits of torn media, may also interfere with the function of an online spectrophotometer. Failure to protect the spectrophotometer from such contamination may result in inaccurate or inconsistent colors, decreased customer satisfaction and increased cost of ownership.